Properties of Novel Components of Polysaccharides Isolated From Lycium barbarum Fruits

This study has established structure‐function relationships of Lycium barbarum polysaccharides (LBPs) relevant to antioxidant and tyrosinase‐inhibitory functions in food systems by integrating optimized extraction, stepwise purification, comprehensive structural analysis, and functional verification, offering a novel multimethod approach to explore structure‐based mechanisms of bioactivity. Firstly, hot‐water extraction optimized at 30 mL/g, 90°C, and 5 h yielded 7.44 % ± 0.17 % crude LBPs. Secondly, ion‐exchange followed by gel‐filtration chromatography separated two purified fractions: LBP‐1 (115.1 kDa) and LBP‐2 (73.5 kDa). LBP‐1 exhibited a compact morphology and featured spectral characteristics indicative of a triple‐helix structure, along with both α ‐ and β ‐glycosidic linkages. In contrast, LBP‐2 showed a more amorphous configuration without triple‐helix features and predominantly β ‐linkages. Their monosaccharide profiles also differed, with LBP‐1 enriched in glucose, mannuronic acid, galacturonic acid, and glucuronic acid, while LBP‐2 contained glucose, galacturonic acid, mannuronic acid, and arabinose. Both fractions exhibited in vitro antioxidant and tyrosinase‐inhibitory activities, with LBP‐2 demonstrating relatively stronger effects. The enhanced performance of LBP‐2 may be associated with its dispersed structure and uronic acid–rich β ‐linked motifs, which increase the accessibility of functional sites. These insights support the potential application of both LBP‐1 and LBP‐2 in functional foods, with LBP‐2 showing greater promise for use in beverages and fresh‐cut fruit products requiring natural antibrowning and antioxidant solutions.